Chapter 3. Scenario overview and design 77
3.3 Technical design
This section discusses the technology and system designs that we used to
architect the scenario.
3.3.1 System architecture
We used WebSphere Business Integration Server Foundation for our application
server and the Business Process Container for our BPEL business processes.
The client makes requests from a Web application through a firewall into the
ITSO Trading Firm trading system. A service proxy object initiates the request
with the trading systems BPEL-based critical business process.
The stock broker is an internal system. However, it is at a remote location that is
also running WebSphere Business Integration Server Foundation and BPEL
processes.The back-end system that provides the stock trade services is an IMS
system that is running on z/OS.
The stock quote and analysis is provided by business process and is an external
system. Access to the stock quote information has to go through a firewall and
interact with a BPEL based business process that is running on WebSphere
Business Integration Server Foundation.
Figure 3-10 on page 78 shows the view of the system and the technology that we
used for the solution. There are services running in the Business Process
Container in WebSphere Business Integration Server Foundation. There are J2C
resource adapters running in managed mode on the application server to access
external and remote systems. The system uses various transport protocols to
interact with the different systems.
78 Managing Information Access to an EIS Using J2EE and Services Oriented Architecture
Figure 3-10 Scenario technical architecture view
3.3.2 Scenario architecture
This section discusses the scenario architecture for each part of the system and
the options that exist in developing them. It illustrates the architecture and
integration patterns for the Internet Trading System, Validate Stock, Stock
Broker, and Stock Analysis Service.
For this scenario we plan on creating three proof points while illustrating a
service-oriented architecture interaction. These points include using JMS
technology to access or interact with an EIS system and using J2C to access an
EIS, which is two forms. One of the J2C interactions is connecting to an IMS
System, the other to a CICS system. Finally, there is a SOAP-based interaction
with an EIS which leverages the WebSphere Business Integration Adapter
portfolio.
WAN (Wide Area Network)
WBI
Adapter
Stock
Quote
Repository
Validate
Adapter
Service
System
Process
Retrieve
Stock
Business Process Container
Stock Analysis (External)
Analysis
Business Process Container
WebSphere Business Integration
Server Foundation
Internet Trading System
Order
Process
Debit
Service
Trading
Process
System
Process
Validate
Stocks
JCA CICS
IMS
JMS
System
Process
JCA
Messaging
JMS
Business Process Container
Stock Broker (REMOTE)
F
F
i
i
r
r
e
e
w
w
a
a
l
l
l
l
Firewall
Firewall
System View
WebSphere Business Integration
Server Foundation
WebSphere Business Integration
Server Foundation
Chapter 3. Scenario overview and design 79
The sections that follow discuss the systems for the scenario and the
architecture of solutions that can provide the three proof points.
Internet Trading System
The Internet Trading System scenario involves a BPEL process that runs on
WebSphere Business Integration Server Foundation. It has sub services
implemented as BPEL processes.
Figure 3-11 shows the Internet Trading System that runs in WebSphere Business
Integration Server Foundation Business Process Container. The interactions for
the service proxy can be a partner link or the use of a proxy object, depending on
implementation.
Figure 3-11 Internet Trading System process trade shares
The main process trade shares handles the coordination and business logic for
the buy shares use case scenario. It interacts with the banking service to
withdraw and deposit money in the customer’s account for the transactions. It
uses the validate service to validate a company stock prior to submitting the
Internet Trading System
Trade
Shares
Services
Stock
Analysis
Service
Service Interface
Validate
Stock
Place
Order
Service
Banking
Services
WSDL
Get Stock Info
WSDL
Debit
Credit
WSDL
Validate
WSDL
Buy
Sell
WSDL
Buy
Sell
WebSphere Business Integration
Server Foundation
Process Execution Container
CBP
Service
Proxy
Service Interface
Service Interface
Service Interface
Service Interface
CBP CBP
CBP
CBP
Service
Proxy
Service
Proxy
CBP - Critical Business Process
80 Managing Information Access to an EIS Using J2EE and Services Oriented Architecture
order and uses the stock analysis service to retrieve the stock information. The
place order service executes the order request.
Looking at the trading system process as a whole, it fits into the service-oriented
architecture solution as the application services business functions. This
component is the core component of the business functionality which should be
agnostic to the technology that is used in providing the services.
These critical business processes are bound together using service proxies that
can be decided upon at deploy time.
Validate Stock
The Validate Stock process in this scenario involves a BPEL process that runs
on WebSphere Business Integration Server Foundation. It determines whether
the company stock submitted is a valid stock for trading within the ITSO Trading
Firm.
Figure 3-12 shows the Validate Stock process.
Figure 3-12 Validate Stock
The Validate Stock process is a critical business process that is used to
orchestrate the validation of the company stock. The system process validate
makes the call to the CICS EIS Trader Application via JCA to retrieve the
company listing. Here again, the application services business functionality is
de-coupled from the information services layer, reinforcing the defense in layers
principle. “EIS system process” on page 48 discusses briefly the
defense-in-layers approach.
Validate Stock
CICS
Trader
App
CBP - Critical Business Process
SP - System Process
Validate
Stock
CBP
WebSphere Business Integration
Server Foundation
Validate
SP
CICS
JCA
Chapter 3. Scenario overview and design 81
Stock Broker (Place Order Service)
The Stock Broker process is a logical system with a remote physical component.
It consists of a BPEL process which resides in the same system as the trading
system. Requests to the stock broker application are made asynchronously from
the Place Order Service.
Figure 3-13 shows the Place Order Service process.
Figure 3-13 Place Order Service
The Place Order process uses the Send Order Request system process to
submit an order via WebSphere MQ over JMS to the stock broker application
running on a remote server over the intranet. The message is retrieved by the
system process from the message store and sent to the IMS based stock broker
application.
The implementation of this solution uses two WebSphere MQ JMS providers to
send messages between each other. A message is placed on the local queue,
then the queue manager through channels transfer the message to the remote
WebSphere MQ JMS provider.
This solution could have been implemented differently by putting the message
directly on the remote queue to provide for fault tolerance if the remote system is
down. This setup allows the trading system to complete the transaction of the
buy or sell order without disrupting the customers request during a brief failure of
the external system. So, this solution provides both an asynchronous mechanism
Place Order Service
IMS
JCA
Intranet
WSDL
Buy
Sell
Service Interface
Place
Order
Service
CBP
MQ
JMS
(EIS)
IMS
Send
Order
Request
SP
MQ
JMS
P
r
o
v
i
d
e
r
MQ Transport
MQ
JMS
P
r
o
v
i
d
e
r
Submit
Order
SP
Remote - Stock Broker
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